1. Field of the Invention
The present invention relates to a technique for an image processing device, and in particular, a technique for display of an image subjected to correction based on a point spread function (PSF).
2. Description of the Related Art
Image deterioration or diffraction blur resulting from various types of aberration for an optical system (photographing lens and the like) may occur in a photographic image obtained by photographing an object by an image-capturing device, such as a digital camera.
In order to prevent image deterioration or diffraction blur (peripheral blur, chromatic aberration of magnification, or the like) resulting from aberration, a technique which subjects image data of an object image to an image process to remove (correct) image deterioration or diffraction blur has been considered.
Image deterioration due to aberration can be expressed by a point spread function (PSF), and image quality can be recovered by subjecting a photographic image with deteriorated image quality to a point-image restoration process based on the point spread function. That is, the point-image restoration process is a process for applying a restoration filter (reverse filter) of the point spread function to photographic image data to cancel image deterioration.
When correcting a photographed photographic image, various techniques for confirming the effect of the correction have been considered.
For example, JP2009-213044A discloses a technique which compares and displays an image after image shake correction and an image before image shake correction.
JP2004-205802A discloses a technique which displays a shaking image before a recovery process and a recovered image after a recovery process, information relating to a point function (considered to correspond to a point spread function of this application), and shake locus data in association with one another.
JP2009-77202A discloses a technique which displays an image to be corrected (an image before correction) and an image after correction, evaluates the degree of restoration of the target image to determine the degree of blurring, and further uses the determination for correction.
JP2011-193277A discloses a technique which displays an area where the difference between images before and after a recovery process (considered to correspond to a point-image restoration process of this application) is maximized, and confirms the effect of the recovery process.